X100 aperture opening

With current X100 firmware, in Aperture priority and Manual setting if we set the aperture to say f/8 the lens will stay at full opening before we half press the shutter. So it takes a few second for the lens to open at the desired opening. This sometime makes us lost precious moment especially in street photography. I wish that Fuji can change the firmware so that when we set aperture at say 8, the lens stay open at 8 at all time.